Is there a multiple choice?
Answer:
Explanation:
1) The time of flight equation for projectile motion can be used here to find total time in air.
t = 2vsin∅ / g
where v is speed, Ф is launch angle
t = 2×4×sin 60 / 9.8
t = 0.71 seconds
2) Distance where it hit the ground is called as range and has the following standard equation
D = v² sin2Ф/g
D = 4²sin 2×60 / 9.8
D = 1.41m
3) Maximum elevation is maximum time reached
h = v² sin²Ф / 2g
h = 4²sin² 60 / 2*9.8
h = 0.61 m
Answer:
θ = 45º
Explanation:
The light that falls on the second polarized is polarized, therefore it is governed by the law of Maluz
I = I₀ cos² θ
in the problem they ask us
I = ½ I₀
let's look for the angles
½ I₀ = I₀ cos² θ
cos θ = √ ½ = 0.707
θ = cos 0.707
θ = 45º
Answer:
Explanation:
Given
half life 
billion year
10 % to decay i.e. 90 % remaining
And 
where k= constant
t=time
and 
so 
t=0.684 billion year
(b)
t=13.8 billion year
atoms
Using Newton's law that F = ma.
The force here is the net force. The forces acting in opposite direction are the weight and the air resistance. The weight of course is acting downwards and the air resistance is pushing upwards.
Therefore:
W - AR = ma W = Weight = mg, AR = Air Resistance = 150.
g = 10 m/s2
mg - AR = ma
60(10) - 150 = 60a
600 - 150 = 60a
450 = 60a
60a = 450
a = 450/60
a = 7.5 m/s2
Cheers.
